FIGURE 5.

CTS promotes mitochondrial biosynthesis via the AMPK/SIRT1/PGC-1α signaling pathway. HaCaT cells and HFF-1 cells were treated with CTS (0, 0.02, 0.05, 0.1 μM) for 4 h and irradiated with UVB (200 mJ/cm²) or UVA (15 J/cm²), respectively. Then, the cells were supplemented with the corresponding doses of CTS and incubated for another 0.5 h before analysis. (A) Protein levels of p-AMPK, SIRT1 and PGC-1α in HaCaT cells as measured by western blot. The plots beside the blots show the relative expression levels of p-AMPK, SIRT1 and PGC-1α as determined by grayscale analysis of the bands in the blots. (B) Protein levels of p-AMPK, SIRT1 and PGC-1α in HFF-1 cells as measured by western blot. The plots beside the blots show the relative expression levels of p-AMPK, SIRT1 and PGC-1α as determined by grayscale analysis of the bands in the blots. All data are mean ± SD from three independent experiments, “##” indicates significantly different from the control (no irradiation and CTS treatment) at the p < 0.01 level, whereas “*” and “**” indicate significantly different from the UV-irradiated cells without CTS pretreatment at the p < 0.05 and p < 0.01 levels, respectively.